I have my own custom shower and screen objects so I don't use the standard GS ones and have no idea what they can and can't do.
What about just a standard thin wall with a glass building material (surface).
Barry.
One of the forum moderators.
Versions 6.5 to 27
i7-10700 @ 2.9Ghz, 32GB ram, GeForce RTX 2060 (6GB), Windows 10
Lenovo Thinkpad - i7-1270P 2.20 GHz, 32GB RAM, Nvidia T550, Windows 11